Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond the readOnlyHint/openWorldHint/idempotentHint annotations, the description discloses return states (sanctioned true/false/null), coverage asymmetry, and the fact that null means 'unchecked, not clean.' This is valuable behavioral context that could not be inferred from the schema or annotations alone.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Four sentences with no filler: the primary action comes first, followed by format coverage, the edge case, and the scope caveat. Each sentence earns its place and is appropriately compact for a single-parameter lookup tool.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-address read-only lookup with no output schema, the description fully equips the agent: input formats, output semantics, coverage limitations, and the caveat that this is not a comprehensive risk score. Nothing critical is missing for correct invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3, but the description adds meaning by explaining what 'covered' means for each address format and what outcomes result. It connects the address parameter to the tool's behavioral output more clearly than the schema's pattern descriptions alone.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific verb ('Screens') and resource ('crypto address against every OFAC SDN digital currency address list'), and explicitly scopes the output as a sanctions signal rather than a full risk score. This is clearly distinct from the sibling tools by domain and purpose.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description makes clear what the tool is for and when its coverage is authoritative (EVM and Bitcoin) versus partial (other chains). It also sets expectations for Cosmos bech32 addresses, though it does not explicitly name alternative sibling tools for deeper or broader risk assessments.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.